Process of positioning automotive components

ABSTRACT

A process and system for measuring, positioning and welding a bracket  30  to a mounting surface, such as a vehicle side rail  40 , to accomplish smooth and continuous bracket assembly. A bracket positioning tool  20  on a robotic arm  10  allows brackets  30  to adjust to minimize the gap between the bracket  30  and its intended mounting surface. The bracket positioning tool  20  positions brackets  30  near the surface, and allows brackets  30  to adjust for a precise surface match. With input from a second measurement, a welding robot  50  welds the bracket  30  to the surface with the gap minimized while the bracket  30  is held in position. The measurement system and bracket positioning with flexible tooling do not require the bracket  30  to be forced with pressure against the mounting surface. With robots, brackets can be consistently placed and welded in precise locations on varying mounting surfaces.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and all benefits of U.S. Provisional Application 61/944,013, filed on Feb. 24, 2014, entitled “Pivoting Tool for Positioning Automotive Components and Method Thereof”, which is incorporated herein by reference.

FIELD OF THE DISCLOSURE

This disclosure relates a bracket positioning process, specifically, for measuring positions and placing an automotive component, such as a bracket, in a desired position, with a measurement system and a bracket positioning tool, such as a pivoting tool, before welding the component to a vehicle chassis frame, preferably using input from further measurements.

BACKGROUND

In large welding operations, such as those present in the automotive industry, high flexibility operations are a significant concern. Flexibility is pursued by creating tools and operations that may be utilized for welding several different components and by simplifying the equipment and devices to be more versatile and less costly.

In a cell, the frame position varies with each bracket due to the nature of the operation. The position of the frame and the position where the bracket must be placed can vary with each frame coming through the cell. Each entering frame does not arrive exactly at the same spot of the cell. Variations of a few millimeters are common, and such variations can adversely affect the bracket positioning and the final assembled frame with a mounted bracket.

Many tooling efforts have been developed for creating more flexible welding operations regarding structural chassis frames, specifically, for those components that are attached to the main side rails, such as steel brackets. Welding operations usually demand specialty tools. In the case of the brackets, it is common practice to secure brackets in their desired position by using a lineal pneumatic arm, which keeps the brackets at the desired position by pressing the bracket into the component to which it will be welded. This less flexible tool is a dedicated fixed unique station that slides and then presses the bracket against the side rail.

In high volume welding operations, such as those present in the automotive industry, where several formed components proceed into welding processes, it is common to find variations in the geometry of materials according to specification tolerances. To optimize the joining of components, the welding processes must guarantee that a variation within formed components does not affect the welding precision and therefore, it is common to make adjustments in the tooling placement.

Tools designed to place a component, such as a bracket, into a desired position by utilizing force, such as pneumatic force, are usually oversized and expensive tools.

The present disclosure describes a positioning tool and its corresponding method to guarantee that an automotive component, such as a bracket, is placed within a desired position without the need of utilizing oversized and costly specialty tooling.

SUMMARY AND OBJECTS OF THE DISCLOSURE

The present disclosure is directed to bracket placement and welding processes. The measuring, component positioning and welding allows for precise positioning and a minimal space gap between the automotive components to be welded, such as a bracket with the surface to where the component is to be welded, such as a vehicle chassis frame side rail.

In the overall bracket positioning process, an adjustable tool from the present disclosure is attached to a robotic arm, wherein the robotic arm takes a bracket from a bracket pool. The robotic arm is then automated to place the bracket in a specific position on a vehicle side rail surface. A pivoting tool can automatically pivotal to guarantee that the gap between the bracket and the side rail is minimized.

The preferred process uses an initial measurement system that as a first major step reads the exact position of the frame and the position where the bracket must be placed when the frame enters the working cell. The measurements from the measurement system are the input for the bracket positioning step.

The measurement system reads the exact position of the frame and then where the bracket will be placed and mounted. The bracket positioning input can differ for each frame coming through the cell.

Next, the tool receives the bracket positioning input from the initial measurements, adjusts the bracket position based on the initial measurements, uses software code for “offsetting robot positions”, and uses the measurement system to position the robot that is holding brackets.

After the bracket position is optimized, a welding robot approaches the gap between the bracket and the side rail and welds both components together. In the third major step of welding the bracket, a welding robot preferably receives input from the second measurement of the gap and welds the bracket at the desired position using the measurement input.

The present disclosure provides an adjustable tool characterized by being able to be attached to a robotic arm, wherein the tool has the ability to adjust and pivot and wherein such adjustment guarantees that the surface gap caused by geometric variations within tolerance, gets positioned wherein the welding operation is optimized.

Even though the frame position varies with each bracket due to the nature of the operation, the same spot can be determined where each frame arrives at the cell. Variations are common due to heating and forces on the mounting surface, for example, and such variation affects the bracket positioning. Variations of just a couple millimeters can be avoided with the measuring, bracket positioning, and welding of the bracket, preferably based on multiple measurements.

It is therefore an object of the present disclosure to provide tools and a method that measures and minimizes the gap between two components that are going to be welded together without the need to utilize force to guarantee positioning of the components. Measurement, bracket positioning and welding with an adjustable robot accomplish a smooth and continuous bracket assembly with precise and consistent bracket placement on varying frames.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features of this disclosure and the manner of obtaining them will become more apparent, and the disclosure itself will be best understood by reference to the following descriptions of tools and processes taken in conjunction with the accompanying figures, which are given as non-limiting examples only, in which:

FIG. 1 is a perspective view of an adjustable tool attached to a robotic arm as described in the present disclosure;

FIG. 2 is a perspective view of the adjustable tool without a bracket on a robotic arm;

FIG. 3 is a top view of the adjustable tool showing pivoting of a bracket to adjust to surface changes that may be on the surface to which the bracket may be welded;

FIG. 4 is a perspective view of the larger system with the robotic arm placing a bracket adjacent to a side rail for welding; and

FIG. 5 is a perspective view of a combination end with a bracket loading pivoting tool, a measurement system, and a welding robot.

The exemplifications set out herein illustrate embodiments of the disclosure that are not to be construed as limiting the scope of the disclosure in any manner. Additional features of the present disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the disclosure as presently perceived.

DETAILED DESCRIPTION

While the present disclosure may be susceptible to embodiments in different forms, the figures show, and herein describe in detail, embodiments with the understanding that the present descriptions are to be considered exemplifications of the principles of the disclosure and are not intended to be exhaustive or to limit the disclosure to the details of construction and the arrangements of components set forth in the following description or shown in the figures.

After the frame, such as a side rail 40, gets to the cell, a measurement system 44 mounted on either the robot or any part of the cell reads the exact position of the frame and the position where the bracket 30 must be placed. Even though the frame position varies with each bracket due to the nature of the operation, the same spot can be determined where each frame arrives at the cell. The measurements from the measurement system 44 are the input for the bracket positioning step.

Next, the tool receives the bracket positioning data from the initial measurements, and the bracket positioning is adjusted based on the initial measurements and uses software code for “offsetting robot positions” and uses another measurement system to position the robot that is holding brackets. The robot positions the bracket 30 to adjust for slight variations of each frame in the cell.

A bracket positioning tool 20, such as an adjustable pivoting tool, can be used as part of a robotic system with a moveable arm, such as a preferred robotic arm 10 that can move on six axes. Unlike a bracket being forced against a mounting surface for welding with pressure, the adjustable tool 20 ensures surface match of the bracket 30 against a mounting surface without significant force or loosening of a tool while allowing for slight height variance, preferably adjusted by the initial measurements of the measurement system 44. The adjustable tool 20 adjusts for surface change and variations. Surface gap is avoided with specific matching against varying mounting surfaces, which may vary with heat distortion or other conditions.

As shown in FIG. 1, an adjustable tool 20 attached mechanically to a robotic arm 10 grabs a component, such as a bracket 30, and wherein the adjustable tool 20 allows the bracket 30 to move about or around a specific axis to minimize the surface gap between the bracket 30 and the surface to which the bracket 30 is to be welded, such as a side rail 40. The adjustable tool 20 preferably pivots relative to an appendage 12 or base on the robotic arm 10. In a preferred embodiment, the adjustable tool 20 is characterized by having vision or strength sensors 14 to guarantee that the bracket 30 is positioned at a desired place. The second measuring system 48 can be associated with the sensors 14, such as a vision system, which provide input for the bracket welding step. The second measurement of the bracket 30 can provide input that is provided to a welding robot to weld exactly where the bracket 30 is positioned.

As shown in FIG. 2, the adjustable tool 20 pivots around a pivot pin 16 relative to the appendage 12. The appendage 12 is preferably attached on a distal end of the robotic arm 10, and the appendage 12 allows for precise movement of the bracket 30. The appendage 12 can be adjustable to allow for height variations or slight adjustments, such as by a height adjustor 22 that moves linearly relative to the robotic arm 10. Various vision and strength sensors 14 can observe, detect, perceive and/or determine placement, force and location for adjustment based on preprogrammed code controlling the placement of the bracket 30 relative to the side rail 40 as an example.

FIG. 2 shows the adjustable tool 20 as the portion that pivots around the pivot pin 16 in a detailed component. This exemplary adjustable tool 20 has at least one grip 18 that grasps, secures, clamps or otherwise holds the bracket 30 as it can be retrieved from a bracket pool, positioned, held, and welded to a side rail 40. Preferably, a grip 18 holds each side of the bracket 30, depending on the configuration of the bracket 30. The bracket 30 is released from the adjustable tool 20 after it is welded to the side rail 40.

FIG. 3 shows how the bracket 30 can automatically pivot to adjust to surface changes or variations that may be on the surface of the side rail 40 to which the bracket 30 may be welded. The bracket 30 can pivot about an axis of the pivot pin 16 to adjust as needed, as would minimize the space or surface gap between the bracket 30 and a side rail 40 to which it is intended to be welded.

The adjustable tool design allows for the bracket 30 to adapt to changes, ensuring surface match with the mounting surface of the side rail 40 through adjustments and pivoting positioning via the adjustable tool 20 without using substantial force against the mounting surface or loosening of the tooling that allows for height variations or other slight adjustments.

According to the present disclosure, the process of positioning the bracket 30 at the desired position for welding involves securing the bracket 30, such as taking a bracket 30 from a bracket pool, measuring the exact position of the frame and bracket placement location, positioning the bracket 30 adjacent to the desired surface with a robotic arm 10 using the measurement input, minimizing the space gap between the bracket 30 and the side rail 40 through adjusted positioning via an adjustable tool 20, preferably by using sensors 14 (i.e. vision and strength) for another measurement. Then the bracket 30 is welded to the side rail 40 while the bracket 30 is held in the desired position. The welding robot 50 preferably receives input from the second measurement system 48 and precisely welds the bracket 30 at the desired position on the frame. Throughout the step of welding, the gap is minimized between bracket 30 and the mounting surface. The precise measuring and smaller gap should use less welding material.

In more detail, the process of placement before welding a bracket 30 to a mounting surface includes the adjustable tool 20 securing and positioning the bracket 30 at a desired position close to the mounting surface, minimizing the gap between the bracket 30 and the mounting surface via pivoting of the adjustable tool 20, automated movement of the robotic arm 10, and possible adjustment by an appendage 12 between the adjustable tool 20 and the end of the robotic arm 10.

FIG. 4 shows positioning the bracket 30 near the desired mounting surface of the side rail 40 at an appropriate location to be welded. With a minimal gap between the bracket 30 and the side rail 40, a welding robot 50 is set to weld the bracket 30 to the side rail 40 while the bracket 30 is held in the desired position by the adjustable tool 20 on the robotic arm 10.

The positioning and welding system for welding a bracket 30 to a mounting surface uses the adjustable tool 20 on a robotic arm 10 to allow the bracket 30 to pivot on an axis to minimize the gap between the bracket 30 and its intended mounting surface.

The adjustable tool 20 can use its grip 18 to secure the bracket 30. The robotic arm 10 moves the adjustable tool 20 near the mounting surface. A pivot pin 16 ideally allows the adjustable tool 20 to pivot relative to a preferred appendage 12 on the distal end of the robotic arm 10. The appendage 12 may have a height adjustor 22 to precisely move the bracket 30 linearly relative to the robotic arm 10. The system allows the bracket 30 to move and pivot for a precise surface match with the mounting surface without being forced with substantial pressure against the mounting surface. Input from the measurement system 44 can automatically adjust the adjustable tool 20 or the adjustable tool 20 can be placed in close proximity to the mounting surface with slight or no pressure, and then may be measured by another measurement system 46 regarding the gap. A welding robot 50 welds the bracket 30 to the mounting surface with the gap minimized while the bracket 30 is held in the desired position.

In the bracket positioning step, the measurement system 46 can receive the bracket positions from the first step and can use software code for “offsetting robot positions.” One or more measurement system 44, 46 or 48 ideally measures and positions the robotic arm 10 and thus the bracket 30 relative to the side rail 40.

In the bracket welding step, a welding robot 50 preferably receives input from the second measurement system 46 or 48, such as measuring the gap, and precisely welds the bracket 30 at the desired position on the mounting surface, such as a side rail 40. The second measurement system 46 or 48 can preferably be a vision system.

FIG. 5 shows a combination end 60 with a bracket-loading adjustable tool 20, a second measurement system 46 and/or 48, and a welding robot 50 incorporated into a single tool adapted to operate on a distal end of the robotic arm 10. The welding robot 50 as shown can move in all directions relative to the base of the combination end 60, and the adjustable tool 20, which would be stationary during welding to hold the bracket 30 in place with the adjustable tool 20. While requiring specialized combination tooling, the robotic arm 10 with the combination end 60 can handle both placement and welding functions to avoid a second robot, requiring less floor space.

This disclosure has been described as having exemplary embodiments and is intended to cover any variations, uses, or adaptations using its general principles. It is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the scope of the disclosure as recited in the following claims. Further, this disclosure is intended to cover such variations from the present disclosure as come within the known or customary practice within the art to which it pertains. 

What is claimed is:
 1. A process of welding a bracket to a mounting surface including using an adjustable tool on a moveable arm that allows the bracket to adjust to minimize gap between the bracket and its intended mounting surface, comprising the steps of: securing the bracket via the moveable arm; measuring current position of the mounting surface and current position where the bracket is to be placed; positioning the bracket at a desired position adjacent to the mounting surface based on measurements of the positions; minimizing the gap between the bracket and the mounting surface through positioning via the adjustable tool, measuring the position of the bracket and providing positioning input to a welding robot to precisely weld the bracket to the mounting surface, and welding the bracket to the mounting surface using the welding robot with the gap minimized while the bracket is held in the desired position.
 2. The process of claim 1 including a step of using vision sensors to observe, detect, perceive or determine positioning of the bracket, and positioning the bracket with a robot.
 3. The process of claim 1 wherein surface match of the bracket to the mounting surface does not require the bracket to be forced with substantial pressure against the mounting surface, and the height of the bracket relative to the mounting surface is adjusted by an adjustable appendage on which the adjustable tool is mounted on a distal end of the moveable arm based on input from measuring the current position.
 4. A method of manufacturing vehicle side rail with a bracket welded on a portion of the side rail using a measuring system, a bracket positioning tool and a welding robot, the method comprising the steps of: securing the bracket with the bracket positioning tool on an end of a moveable arm; moving the end of the moveable arm toward the side rail; measuring current position of the side rail and current position where the bracket is to be placed positioning the bracket adjacent to the side rail; minimizing a gap between the bracket and the side rail through adjustments via the bracket positioning tool that allows the bracket to adjust; measuring the gap and providing measurement input to the welding robot, and welding the bracket to the side rail using the welding robot with the gap minimized while the bracket is held precisely in position throughout the welding.
 5. The method of claim 4 further includes adjusting the bracket linearly with an appendage located between the bracket positioning tool and the end of the moveable arm, wherein the appendage adjusts based on measurements of the side rail and the bracket.
 6. The method of claim 4 further comprising a step of using vision sensors to observe, detect, perceive or determine positioning of the bracket.
 7. The method of claim 4 wherein the welding robot is also mounted on the moveable arm as a combination end adapted to operate on the distal end of the moveable arm, and the welding robot moves relative to the bracket positioning tool, which is stationary during welding to hold the bracket in place.
 8. A process of welding a bracket to a mounting surface including using a robotic arm that allows the bracket to adjust to minimize gap between the bracket and its intended mounting surface, comprising the steps of: securing the bracket via the robotic arm; measuring current position of the mounting surface and current position where the bracket is to be placed; providing data of the positions to the robotic arm; positioning the bracket at a desired position via the robotic arm adjacent to the mounting surface based on measurements of the positions with minimal the gap between the bracket and the mounting surface, measuring the position of the bracket and providing positioning input to a welding robot to precisely weld the bracket to the mounting surface, and welding the bracket to the mounting surface using the welding robot with the gap minimized while the bracket is held in the desired position.
 9. The process of claim 8 including using vision sensors to observe, detect, perceive or determine positioning of the bracket. 